Doing the below will reproduce my problem:
Maybe this helps?
Private Sub LstView_MouseDoubleClick(ByVal sender As Object, ByVal e As System.Windows.Input.MouseButtonEventArgs) Handles LstView.MouseDoubleClick
Dim source As FrameworkElement = TryCast(e.OriginalSource, FrameworkElement)
If IsNothing(source) Then Return
Dim TmplParent As DependencyObject = TryCast(source.TemplatedParent, DependencyObject)
If IsNothing(TmplParent) Then Return
If Not TmplParent.GetType.Equals(GetType(System.Windows.Controls.ListViewItem)) Then e.Handled = True
End Sub